Psoriatic arthritis is a heterogeneous chronic inflammatory disorder involving joints, tendon sheaths, entheses, and the axial skeleton as well as skin and nails. This is an open-label trial with H.P. Acthar Gel (80 units/1mL) Subcutaneous injection administered twice weekly. To evaluate the signs and symptoms of psoriatic arthritis after 12 weeks, including American College of Rheumatology 20,Clinical Disease Activity Index, Disease Activity Index 28, Dactylitis and adverse events.